A method is described for preparing a tricondensate polyfunctional isocyanate composition, preferably having at least an isocyanurate and/or biuret group, which includes adding to a tricondensate polyfunctional isocyanate, or a mixture of different tricondensate polyfunctional isocyantes, obtained by (cyclo)condensation, in particular (cyclo)trimerization of one or several identical or different isocyanate monomers and optionally of another monomer, an allophanate of one or several identical or different isocyanates, or a mixture of different allophanates. The isocyanates or isocyanate monomer mixtures used for preparing the polyfunctional isocyanate(s) may be identical to or different from the isocyanate(s) or isocyanate mixture used for preparing the allophanate(s).